Leonardo da Vinci could visually flip between dimensions, neuroscientist claims

A neuroscientist argues that Da Vicni shared a disorder with Picasso and Rembrandt.

  • A neuroscientist at the City University of London proposes that Leonardo da Vinci may have had exotropia, allowing him to see the world with impaired depth perception.
  • If true, it means that Da Vinci would have been able to see the images he wanted to paint as they would have appeared on a flat surface.
  • The finding reminds us that sometimes looking at the world in a different way can have fantastic results.

An analysis of Renaissance artwork suggests that Leonardo Da Vinci may have had exotropia, a kind of strabismus which causes one of the eyes to be turned outwards, and that the condition may have helped him as a painter by allowing him to switch between three-dimensional and two-dimensional vision. He wouldn't have been alone, other famous painters who are speculated to have had the condition include Rembrandt and Picasso.

The study

Vitruvian Man, by Leonardo da Vinci created c. 1480–1490

The Virtuvian Man. Christopher Tyler suggests that Da Vinci used his own image as a template for the face in the drawing.

Professor Christopher Tyler of the City University of London's optometry division analyzed six pieces of Renaissance art by or held to be images of Da Vinci, including the famous Vitruvian Man. By looking at the paintings, drawings, and statues and applying the same techniques optometrists use on patients, Tyler was able to conclude that the eyes of the men depicted were misaligned.

He concluded that, if the images he analyzed were truly reflective of how Da Vinci looked, that the great artist had a mild case of exotropia.

How would this have helped him paint?

Shira Robbins, a professor of ophthalmology at the University of California at San Diego, who was not involved with the project, explained to The Washington Post how individuals with exotropia often turn to additional information to help understand the world around them:

"What happens in some people is when they're only using one eye . . . they develop other cues besides traditional depth perception to understand where things are in space, looking at color and shadow in a way that most of us who use both eyes at a time don't really appreciate."

Dr. Robbins agrees that, if the artworks analyzed accurately depict Da Vinci, then he probably had exotropia.

If Da Vinci did have a mild form of the condition, which would allow him to focus with both eyes when concentrating and with one when relaxed, Tyler asserts that the famed artist could have viewed the world in two or three dimensions at will, showing him the world exactly as he would need to recreate it on a flat surface. Quite the superpower for an artist.

Does this mean Da Vinci would have been a hack if he had normal eyesight?

​A graph showing the difference in where each eye is focused for each painting, drawing, and statue used in the study. The larger the difference, the more pronounced the exotropia is in the image. 

Christopher Tyler

Not at all. What Dr. Tyler is suggesting is that the tendency of people who have exotropia to rely on using one eye to see the world and thereby lose some depth perception allowed Da Vinci to understand better how the three-dimensional objects in the world could be translated into a two-dimensional image on a canvas. This could account for some of Da Vinci's skill in depicting shadow and subtle changes in color, since he would have relied on these details to understand the world.

His polymathic brilliance extended far beyond art, and nobody is claiming that his ideas for flying machines, tanks, or other inventions were at all influenced by a vision problem.

How can we know this? He has been dead for five hundred years.

There are reasons to be cautious anytime we make claims about people who are long dead. In this case, we have the bonus problem that we aren't 100 percent sure that the images used are supposed to look like Da Vinci.

That is the major caveat of the idea; all of the images used as evidence of his condition are assumed to look like him. While some of the images, like the David by Andrea del Verrocchio, are generally agreed to be based on Leonardo the other pictures are claimed to be reflective of him based only on his statement that "[The soul] guides the painter's arm and makes him reproduce himself, since it appears to the soul that this is the best way to represent a human being."

Tyler also argues that the portraits he claims are based on Da Vinci share similarities with the images generally accepted to be portraits of him; including similar hair and facial features. This lends weight to the idea that the artist incorporated his own traits into his artwork, including his vision problem.

Leonardo da Vinci was undoubtedly one of the greatest geniuses of all time. If he had exotropia, then it was merely a minor addition to his artistic skills. It does, however, give us a literal example of how people who look at the world differently can use that vantage point to their advantage to create things we all can appreciate.

Big Think Edge
  • The meaning of the word 'confidence' seems obvious. But it's not the same as self-esteem.
  • Confidence isn't just a feeling on your inside. It comes from taking action in the world.
  • Join Big Think Edge today and learn how to achieve more confidence when and where it really matters.
Videos
  • Prejudice is typically perpetrated against 'the other', i.e. a group outside our own.
  • But ageism is prejudice against ourselves — at least, the people we will (hopefully!) become.
  • Different generations needs to cooperate now more than ever to solve global problems.


Yale scientists restore brain function to 32 clinically dead pigs

Researchers hope the technology will further our understanding of the brain, but lawmakers may not be ready for the ethical challenges.

Still from John Stephenson's 1999 rendition of Animal Farm.
Surprising Science
  • Researchers at the Yale School of Medicine successfully restored some functions to pig brains that had been dead for hours.
  • They hope the technology will advance our understanding of the brain, potentially developing new treatments for debilitating diseases and disorders.
  • The research raises many ethical questions and puts to the test our current understanding of death.

The image of an undead brain coming back to live again is the stuff of science fiction. Not just any science fiction, specifically B-grade sci fi. What instantly springs to mind is the black-and-white horrors of films like Fiend Without a Face. Bad acting. Plastic monstrosities. Visible strings. And a spinal cord that, for some reason, is also a tentacle?

But like any good science fiction, it's only a matter of time before some manner of it seeps into our reality. This week's Nature published the findings of researchers who managed to restore function to pigs' brains that were clinically dead. At least, what we once thought of as dead.

What's dead may never die, it seems

The researchers did not hail from House Greyjoy — "What is dead may never die" — but came largely from the Yale School of Medicine. They connected 32 pig brains to a system called BrainEx. BrainEx is an artificial perfusion system — that is, a system that takes over the functions normally regulated by the organ. The pigs had been killed four hours earlier at a U.S. Department of Agriculture slaughterhouse; their brains completely removed from the skulls.

BrainEx pumped an experiment solution into the brain that essentially mimic blood flow. It brought oxygen and nutrients to the tissues, giving brain cells the resources to begin many normal functions. The cells began consuming and metabolizing sugars. The brains' immune systems kicked in. Neuron samples could carry an electrical signal. Some brain cells even responded to drugs.

The researchers have managed to keep some brains alive for up to 36 hours, and currently do not know if BrainEx can have sustained the brains longer. "It is conceivable we are just preventing the inevitable, and the brain won't be able to recover," said Nenad Sestan, Yale neuroscientist and the lead researcher.

As a control, other brains received either a fake solution or no solution at all. None revived brain activity and deteriorated as normal.

The researchers hope the technology can enhance our ability to study the brain and its cellular functions. One of the main avenues of such studies would be brain disorders and diseases. This could point the way to developing new of treatments for the likes of brain injuries, Alzheimer's, Huntington's, and neurodegenerative conditions.

"This is an extraordinary and very promising breakthrough for neuroscience. It immediately offers a much better model for studying the human brain, which is extraordinarily important, given the vast amount of human suffering from diseases of the mind [and] brain," Nita Farahany, the bioethicists at the Duke University School of Law who wrote the study's commentary, told National Geographic.

An ethical gray matter

Before anyone gets an Island of Dr. Moreau vibe, it's worth noting that the brains did not approach neural activity anywhere near consciousness.

The BrainEx solution contained chemicals that prevented neurons from firing. To be extra cautious, the researchers also monitored the brains for any such activity and were prepared to administer an anesthetic should they have seen signs of consciousness.

Even so, the research signals a massive debate to come regarding medical ethics and our definition of death.

Most countries define death, clinically speaking, as the irreversible loss of brain or circulatory function. This definition was already at odds with some folk- and value-centric understandings, but where do we go if it becomes possible to reverse clinical death with artificial perfusion?

"This is wild," Jonathan Moreno, a bioethicist at the University of Pennsylvania, told the New York Times. "If ever there was an issue that merited big public deliberation on the ethics of science and medicine, this is one."

One possible consequence involves organ donations. Some European countries require emergency responders to use a process that preserves organs when they cannot resuscitate a person. They continue to pump blood throughout the body, but use a "thoracic aortic occlusion balloon" to prevent that blood from reaching the brain.

The system is already controversial because it raises concerns about what caused the patient's death. But what happens when brain death becomes readily reversible? Stuart Younger, a bioethicist at Case Western Reserve University, told Nature that if BrainEx were to become widely available, it could shrink the pool of eligible donors.

"There's a potential conflict here between the interests of potential donors — who might not even be donors — and people who are waiting for organs," he said.

It will be a while before such experiments go anywhere near human subjects. A more immediate ethical question relates to how such experiments harm animal subjects.

Ethical review boards evaluate research protocols and can reject any that causes undue pain, suffering, or distress. Since dead animals feel no pain, suffer no trauma, they are typically approved as subjects. But how do such boards make a judgement regarding the suffering of a "cellularly active" brain? The distress of a partially alive brain?

The dilemma is unprecedented.

Setting new boundaries

Another science fiction story that comes to mind when discussing this story is, of course, Frankenstein. As Farahany told National Geographic: "It is definitely has [sic] a good science-fiction element to it, and it is restoring cellular function where we previously thought impossible. But to have Frankenstein, you need some degree of consciousness, some 'there' there. [The researchers] did not recover any form of consciousness in this study, and it is still unclear if we ever could. But we are one step closer to that possibility."

She's right. The researchers undertook their research for the betterment of humanity, and we may one day reap some unimaginable medical benefits from it. The ethical questions, however, remain as unsettling as the stories they remind us of.

Scientists see 'rarest event ever recorded' in search for dark matter

The team caught a glimpse of a process that takes 18,000,000,000,000,000,000,000 years.

Image source: Pixabay
Surprising Science
  • In Italy, a team of scientists is using a highly sophisticated detector to hunt for dark matter.
  • The team observed an ultra-rare particle interaction that reveals the half-life of a xenon-124 atom to be 18 sextillion years.
  • The half-life of a process is how long it takes for half of the radioactive nuclei present in a sample to decay.
Keep reading Show less